A Long Neck and a Big Smile

About this drawing

A cute brachiosaurus may look simple, but its long neck was a real feat of engineering. Think about it. A neck that long would be far too heavy if it were made of solid bone. So how did this dinosaur hold its head up all day?

The answer is air! The bones in its neck were full of hollow spaces, kind of like a hard sponge. That kept them strong but light. Birds have bones like this today, which helps them fly. It's a neat trick, and dinosaurs had it first.

Breathing was a challenge, too. With a neck that long, air had to travel a long way to reach the lungs. Scientists think this dinosaur had air sacs inside its body, just like birds do. These helped move fresh air through its huge frame.

This giant lived about 150 million years ago and spent most of its day eating leaves. Its head was tiny compared to its body, and that kept the neck from getting too heavy. Babies hatched from eggs, and they started out far smaller than their parents. They had a lot of growing to do, and they grew up fast.

• dinosaurs
• brachiosaurus
• preschool
• volcanoes